Endospore Stain Results

Purpose: To differentiate between organisms
that can produce endospores and those that cannot. Also allows differentiation
based on the position of the endospore in the cell

Principle: Spores have a durable
outer coating that is composed of the protein keratin. This keratin
coat resists staining so in order to stain a spore the primary stain, malchite
green, must be heated to drive the stain into the spores. Vegatative
cells are then decolorized with water and 0.5% safranin is used to counterstain.
Thus endospores are stained green, while vegetative cells are stained red.

The stain to the right shows a bacterium capable
of endospore production.A. Vegetative CellB. Endospore